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Plant Foods For Human Nutrition... Mar 2016Dietary fibre has been consumed for centuries with known health benefits, but defining dietary fibre is a real challenge. From a functional perspective, dietary fibre is... (Review)
Review
Dietary fibre has been consumed for centuries with known health benefits, but defining dietary fibre is a real challenge. From a functional perspective, dietary fibre is described as supporting laxation, attenuating blood glucose responses and assisting with cholesterol lowering. The problem is different types of dietary fibre have different effects, and new effects are increasingly observed, such as the influence on gut microbiota. Thus, a single definition may need to be described in more generic terms. Rather than being bound by a few functional definitions, we may need to embrace the possibilities of new horizons, and derive a working definition of dietary fibre based on a set of conceptual principles, rather than the limited definitions we have to date. To begin this process, a review of individual fibre types and their physiological effects would be helpful. Dietary fibre is a complex group of substances, and there is a growing interest in specific effects linked to fibre type. Different fractions of dietary fibre have different physiological properties, yet there is a paucity of literature covering the effects of all fibres. This paper describes a range of individual fibre types and identifies gaps in the literature which may expose new directions for a working definition of dietary fibre.
Topics: Blood Glucose; Cholesterol; Dietary Fiber; Edible Grain; Health; Humans
PubMed: 26847187
DOI: 10.1007/s11130-016-0529-6 -
Journal of Dairy Science Oct 1991There is a need to standardize the NDF procedure. Procedures have varied because of the use of different amylases in attempts to remove starch interference. The original... (Review)
Review
There is a need to standardize the NDF procedure. Procedures have varied because of the use of different amylases in attempts to remove starch interference. The original Bacillus subtilis enzyme Type IIIA (XIA) no longer is available and has been replaced by a less effective enzyme. For fiber work, a new enzyme has received AOAC approval and is rapidly displacing other amylases in analytical work. This enzyme is available from Sigma (Number A3306; Sigma Chemical Co., St. Louis, MO). The original publications for NDF and ADF (43, 53) and the Agricultural Handbook 379 (14) are obsolete and of historical interest only. Up to date procedures should be followed. Triethylene glycol has replaced 2-ethoxyethanol because of reported toxicity. Considerable development in regard to fiber methods has occurred over the past 5 yr because of a redefinition of dietary fiber for man and monogastric animals that includes lignin and all polysaccharides resistant to mammalian digestive enzymes. In addition to NDF, new improved methods for total dietary fiber and nonstarch polysaccharides including pectin and beta-glucans now are available. The latter are also of interest in rumen fermentation. Unlike starch, their fermentations are like that of cellulose but faster and yield no lactic acid. Physical and biological properties of carbohydrate fractions are more important than their intrinsic composition.
Topics: Animal Feed; Animal Nutritional Physiological Phenomena; Animals; Cattle; Dietary Fiber; Fermentation
PubMed: 1660498
DOI: 10.3168/jds.S0022-0302(91)78551-2 -
Nutrition Reviews Apr 2017Digestive health is an expanding area in nutrition research due to the interest in how food components such as fiber affect gastrointestinal tolerance, stool form,... (Review)
Review
Digestive health is an expanding area in nutrition research due to the interest in how food components such as fiber affect gastrointestinal tolerance, stool form, defecation frequency, transit time, and gut microbial composition and metabolic activity. In children, however, digestive health studies that intervene with dietary fiber are limited due to legal and ethical concerns. To better understand if fiber improves digestive health in children, a literature review was conducted to answer the following research question: What are the effect(s) of fiber-containing foods and/or supplements on digestive health outcomes in children? A search of the PubMed database identified a total of 12 studies that fit the inclusion criteria established for this review. Most of the evidence in children shows beneficial effects of partially hydrolyzed guar gum, glucomannan, and bran on digestive health outcomes; however, the existing evidence is not conclusive. Furthermore, limited data exists on the effect of whole-grain sources of dietary fiber, such as oats. Additional well-designed intervention trials are needed to determine whether outcomes of digestive health such as stool form, gastrointestinal tolerance, and stool frequency are improved by increasing the fiber content of children's diets with whole-grain sources.
Topics: Child; Child Health; Dietary Fiber; Gastrointestinal Diseases; Humans
PubMed: 28586481
DOI: 10.1093/nutrit/nuw068 -
Nature Reviews. Gastroenterology &... Feb 2021Epidemiological studies have consistently demonstrated the benefits of dietary fibre on gastrointestinal health through consumption of unrefined whole foods, such as... (Review)
Review
Epidemiological studies have consistently demonstrated the benefits of dietary fibre on gastrointestinal health through consumption of unrefined whole foods, such as wholegrains, legumes, vegetables and fruits. Mechanistic studies and clinical trials on isolated and extracted fibres have demonstrated promising regulatory effects on the gut (for example, digestion and absorption, transit time, stool formation) and microbial effects (changes in gut microbiota composition and fermentation metabolites) that have important implications for gastrointestinal disorders. In this Review, we detail the major physicochemical properties and functional characteristics of dietary fibres, the importance of dietary fibres and current evidence for their use in the management of gastrointestinal disorders. It is now well-established that the physicochemical properties of different dietary fibres (such as solubility, viscosity and fermentability) vary greatly depending on their origin and processing and are important determinants of their functional characteristics and clinical utility. Although progress in understanding these relationships has uncovered potential therapeutic opportunities for dietary fibres, many clinical questions remain unanswered such as clarity on the optimal dose, type and source of fibre required in both the management of clinical symptoms and the prevention of gastrointestinal disorders. The use of novel fibres and/or the co-administration of fibres is an additional therapeutic approach yet to be extensively investigated.
Topics: Biological Availability; Constipation; Diarrhea; Dietary Fiber; Diverticular Diseases; Fermentation; Gastrointestinal Microbiome; Gastrointestinal Transit; Humans; Inflammatory Bowel Diseases; Intestinal Mucosa; Irritable Bowel Syndrome; Micronutrients; Prebiotics; Solubility; Viscosity
PubMed: 33208922
DOI: 10.1038/s41575-020-00375-4 -
Nutrients May 2021Dietary fibre has long been established as a nutritionally important, health-promoting food ingredient. Modern dietary practices have seen a significant reduction in... (Review)
Review
Dietary fibre has long been established as a nutritionally important, health-promoting food ingredient. Modern dietary practices have seen a significant reduction in fibre consumption compared with ancestral habits. This is related to the emergence of low-fibre "Western diets" associated with industrialised nations, and is linked to an increased prevalence of gut diseases such as inflammatory bowel disease, obesity, type II diabetes mellitus and metabolic syndrome. The characteristic metabolic parameters of these individuals include insulin resistance, high fasting and postprandial glucose, as well as high plasma cholesterol, low-density lipoprotein (LDL) and high-density lipoprotein (HDL). Gut microbial signatures are also altered significantly in these cohorts, suggesting a causative link between diet, microbes and disease. Dietary fibre consumption has been hypothesised to reverse these changes through microbial fermentation and the subsequent production of short-chain fatty acids (SCFA), which improves glucose and lipid parameters in individuals who harbour diseases associated with dysfunctional metabolism. This review article examines how different types of dietary fibre can differentially alter glucose and lipid metabolism through changes in gut microbiota composition and function.
Topics: Dietary Fiber; Fatty Acids, Volatile; Gastrointestinal Microbiome; Glucose; Humans; Lipid Metabolism
PubMed: 34068353
DOI: 10.3390/nu13051655 -
Central European Journal of Public... Sep 2019Trends in dietary nutrition and their personalization are progress in medical science and point out the necessity of adaptation and development of innovations in health... (Review)
Review
Trends in dietary nutrition and their personalization are progress in medical science and point out the necessity of adaptation and development of innovations in health system. The main objective of this article is to review the role of dietary fibre as prebiotics in nutrition with different functionality, its influence on modulation of intestinal microbiota, which has an essential role in maintenance of healthy organisms in people of all ages.
Topics: Diet; Dietary Fiber; Gastrointestinal Microbiome; Nutritional Status; Prebiotics
PubMed: 31580563
DOI: 10.21101/cejph.a5313 -
Alimentary Pharmacology & Therapeutics Jul 2015Application of modern rapid DNA sequencing technology has transformed our understanding of the gut microbiota. Diet, in particular plant-based fibre, appears critical in... (Review)
Review
BACKGROUND
Application of modern rapid DNA sequencing technology has transformed our understanding of the gut microbiota. Diet, in particular plant-based fibre, appears critical in influencing the composition and metabolic activity of the microbiome, determining levels of short-chain fatty acids (SCFAs) important for intestinal health.
AIM
To assess current epidemiological, experimental and clinical evidence of how long-term and short-term alterations in dietary fibre intake impact on the microbiome and metabolome.
METHODS
A Medline search including items 'intestinal microbiota', 'nutrition', 'diet', 'dietary fibre', 'SCFAs' and 'prebiotic effect' was performed.
RESULTS
Studies found evidence of fibre-influenced differences in the microbiome and metabolome as a consequence of habitual diet, and of long-term or short-term intervention (in both animals and humans).
CONCLUSIONS
Agrarian diets high in fruit/legume fibre are associated with greater microbial diversity and a predominance of Prevotella over Bacteroides. 'Western'-style diets, high in fat/sugar, low in fibre, decrease beneficial Firmicutes that metabolise dietary plant-derived polysaccharides to SCFAs and increase mucosa-associated Proteobacteria (including enteric pathogens). Short-term diets can also have major effects, particularly those exclusively animal-based, and those high-protein, low-fermentable carbohydrate/fibre 'weight-loss' diets, increasing the abundance of Bacteroides and lowering Firmicutes, with long-term adherence to such diets likely increasing risk of colonic disease. Interventions to prevent intestinal inflammation may be achieved with fermentable prebiotic fibres that enhance beneficial Bifidobacteria or with soluble fibres that block bacterial-epithelial adherence (contrabiotics). These mechanisms may explain many of the differences in microbiota associated with long-term ingestion of a diet rich in fruit and vegetable fibre.
Topics: Animals; Bacteroides; Bifidobacterium; Diet; Dietary Fiber; Feeding Behavior; Firmicutes; Gastrointestinal Microbiome; Humans; Male; Metabolome
PubMed: 26011307
DOI: 10.1111/apt.13248 -
Nutrition Research Reviews Dec 2017Research into the analysis, physical properties and health effects of dietary fibre has continued steadily over the last 40-50 years. From the knowledge gained,... (Review)
Review
Research into the analysis, physical properties and health effects of dietary fibre has continued steadily over the last 40-50 years. From the knowledge gained, countries have developed guidelines for their populations on the optimal amount of fibre to be consumed each day. Food composition tables from many countries now contain values for the dietary fibre content of foods, and, from these, combined with dietary surveys, population intakes have been determined. The present review assessed the uniformity of the analytical methods used, health claims permitted, recommendations and intakes, particularly from national surveys across Europe and around the world. It also assessed current knowledge on health effects of dietary fibre and related the impact of different fibre types on health. The overall intent was to be able to provide more detailed guidance on the types of fibre which should be consumed for good health, rather than simply a total intake figure, the current situation. Analysis of data indicated a fair degree of uniformity in the definition of dietary fibre, the method used for analysis, the recommended amount to be consumed and a growing literature on effects on digestive health and disease risk. However, national dietary survey data showed that intakes do not reach recommendations and very few countries provide guidance on the types of fibre that are preferable to achieve recommended intakes. Research gaps were identified and ideas suggested to provide information for more detailed advice to the public about specific food sources that should be consumed to achieve health benefits.
Topics: Adolescent; Adult; Child; Child, Preschool; Dietary Fiber; Digestion; Europe; Female; Health Knowledge, Attitudes, Practice; Health Promotion; Humans; Infant; Male; Nutrition Policy
PubMed: 28676135
DOI: 10.1017/S095442241700004X -
Lancet (London, England) Feb 2019Previous systematic reviews and meta-analyses explaining the relationship between carbohydrate quality and health have usually examined a single marker and a limited... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Previous systematic reviews and meta-analyses explaining the relationship between carbohydrate quality and health have usually examined a single marker and a limited number of clinical outcomes. We aimed to more precisely quantify the predictive potential of several markers, to determine which markers are most useful, and to establish an evidence base for quantitative recommendations for intakes of dietary fibre.
METHODS
We did a series of systematic reviews and meta-analyses of prospective studies published from database inception to April 30, 2017, and randomised controlled trials published from database inception to Feb 28, 2018, which reported on indicators of carbohydrate quality and non-communicable disease incidence, mortality, and risk factors. Studies were identified by searches in PubMed, Ovid MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials, and by hand searching of previous publications. We excluded prospective studies and trials reporting on participants with a chronic disease, and weight loss trials or trials involving supplements. Searches, data extraction, and bias assessment were duplicated independently. Robustness of pooled estimates from random-effects models was considered with sensitivity analyses, meta-regression, dose-response testing, and subgroup analyses. The GRADE approach was used to assess quality of evidence.
FINDINGS
Just under 135 million person-years of data from 185 prospective studies and 58 clinical trials with 4635 adult participants were included in the analyses. Observational data suggest a 15-30% decrease in all-cause and cardiovascular related mortality, and incidence of coronary heart disease, stroke incidence and mortality, type 2 diabetes, and colorectal cancer when comparing the highest dietary fibre consumers with the lowest consumers Clinical trials show significantly lower bodyweight, systolic blood pressure, and total cholesterol when comparing higher with lower intakes of dietary fibre. Risk reduction associated with a range of critical outcomes was greatest when daily intake of dietary fibre was between 25 g and 29 g. Dose-response curves suggested that higher intakes of dietary fibre could confer even greater benefit to protect against cardiovascular diseases, type 2 diabetes, and colorectal and breast cancer. Similar findings for whole grain intake were observed. Smaller or no risk reductions were found with the observational data when comparing the effects of diets characterised by low rather than higher glycaemic index or load. The certainty of evidence for relationships between carbohydrate quality and critical outcomes was graded as moderate for dietary fibre, low to moderate for whole grains, and low to very low for dietary glycaemic index and glycaemic load. Data relating to other dietary exposures are scarce.
INTERPRETATION
Findings from prospective studies and clinical trials associated with relatively high intakes of dietary fibre and whole grains were complementary, and striking dose-response evidence indicates that the relationships to several non-communicable diseases could be causal. Implementation of recommendations to increase dietary fibre intake and to replace refined grains with whole grains is expected to benefit human health. A major strength of the study was the ability to examine key indicators of carbohydrate quality in relation to a range of non-communicable disease outcomes from cohort studies and randomised trials in a single study. Our findings are limited to risk reduction in the population at large rather than those with chronic disease.
FUNDING
Health Research Council of New Zealand, WHO, Riddet Centre of Research Excellence, Healthier Lives National Science Challenge, University of Otago, and the Otago Southland Diabetes Research Trust.
Topics: Dietary Carbohydrates; Dietary Fiber; Humans; Noncommunicable Diseases; Primary Prevention
PubMed: 30638909
DOI: 10.1016/S0140-6736(18)31809-9 -
Lancet (London, England) Aug 1977
Topics: Cellulose; Colon; Colonic Diseases; Dietary Fiber; Humans; Hyperglycemia; Hyperlipidemias; Peristalsis
PubMed: 69940
DOI: No ID Found